Joint Source-Channel Coding with Correlated Interference

IEEE Transactions on Communications (Impact Factor: 1.98). 09/2010; DOI: 10.1109/TCOMM.2012.032012.110185
Source: arXiv

ABSTRACT We study the joint source-channel coding problem of transmitting a
discrete-time analog source over an additive white Gaussian noise (AWGN)
channel with interference known at transmitter.We consider the case when the
source and the interference are correlated. We first derive an outer bound on
the achievable distortion and then, we propose two joint source-channel coding
schemes. The first scheme is the superposition of the uncoded signal and a
digital part which is the concatenation of a Wyner-Ziv encoder and a dirty
paper encoder. In the second scheme, the digital part is replaced by the hybrid
digital and analog scheme proposed by Wilson et al. When the channel
signal-tonoise ratio (SNR) is perfectly known at the transmitter, both proposed
schemes are shown to provide identical performance which is substantially
better than that of existing schemes. In the presence of an SNR mismatch, both
proposed schemes are shown to be capable of graceful enhancement and graceful
degradation. Interestingly, unlike the case when the source and interference
are independent, neither of the two schemes outperforms the other universally.
As an application of the proposed schemes, we provide both inner and outer
bounds on the distortion region for the generalized cognitive radio channel.

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